Abstract : Under the new national military strategy, the Department of Defense (DOD) must be capable of rapidly deploying armed forces to respond to contingency and humanitarian operations around the world. Military strategic airlift aircraft provide the capability to fly the critical, early arriving troops and cargo for overseas deployments. Since DOD is increasingly relying on the C-5 aircraft as its primary airlifter, we assessed the reliability and mission capability of the aircraft and DOD's current plan for modifying the C-5.